[The following account is found in the Martyrs Mirror, pages 420-421. The English translation is from 1886, I have done some slight editing.]
When the believers greatly increased under persecution and the cross, there was in Bavaria a learned priest of the mass named Leonhard Keyser. He examined the writings of Zwingli and Luther and also went to Wittenberg, where he conferred with the doctors and commemorated the Supper with them.
Having returned to Bavaria, he examined the fruits and doctrine of the Anabaptists, as well as of Zwingli and Luther, and joined himself under the cross to the separated cross-bearing church of the Anabaptists in the year 1525. He ministered in this church with great power and zeal, undaunted by the tyranny which arose over the believers in the way of putting to death by drowning or burning.
In the second year of his ministry, Leonhard Keyser was apprehended at Scharding in Bavaria and condemned by the bishop of Passau and other priests to be burned on the Friday before St. Lawrence day, in August of that same year.
Having bound him on a cart, they took him to the fire, the priests going alongside and speaking to him in Latin. But he, on account of the people, answered them in German; even as they had refused to speak to him in German before the court, which he had frequently requested.
When he came out into the field and was approaching the fire, bound as he was he leaned down at the side of the cart and plucked a flower. Speaking to the judge who rode on horseback alongside of the cart, he said: “Lord judge, here I pluck a flower; if you can burn this flower and me you have justly condemned me. But, on the other hand, if you cannot burn me and this flower in my hand, consider what you have done and repent.”
Thereupon the judge and the three executioners threw an extraordinary quantity of wood into the fire, in order to burn him immediately to ashes by the great fire. But when the wood was entirely burnt up, his lifeless body was taken from the fire with no visible sign of injury. Then the three executioners and their assistants built another great fire of wood, which, when it was consumed, his body still remained uninjured, only his hair and his nails were somewhat burnt brown. When the ashes were removed, his skin was found smooth and clear, and the flower in his hand not withered or burnt in the least.
The executioners then cut his body into pieces, which they threw into a new fire. When the wood was burnt up, the pieces lay unconsumed in the fire. Finally, they took the pieces and threw them into the river Inn.
The judge was so terrified by this occurrence that he resigned his office and moved to another place. His chief servant, who was with the judge and saw and heard all this, came to us in Moravia, became our brother and lived and died piously. That it might not be forgotten, our teachers have recorded this as it came from his own lips, and now cause it to be promulgated and made known.